Physics - Modern Physics Question with Solution | TestHub

${\mathrm{hv}}_0=6.2\mathrm{ }\mathrm{eV}, {\mathrm{eV}}_0=5\mathrm{ }\mathrm{eV}$

from Einstein's photoelectric equation

$\mathrm{hv}={\mathrm{hv}}_0+{\mathrm{eV}}_0=\mathrm{ }6.2+5\mathrm{ }=\mathrm{ }11.2\mathrm{ }\mathrm{eV}$

$\Rightarrow \frac{\mathrm{hc}}{\mathrm{\lambda }}=11.2$

$\therefore \mathrm{ }\mathrm{\lambda }=\frac{\mathrm{hc}}{11.2}=1108.9\mathrm{Å}$

It belongs to ultra-violet region.